Paper Chromatography Experiment.

The simplest paper chromatography experiment at home is a paper
chromatography of a black marker. On this page you'll find very simple
setup with
some details that allow you to achieve the best results separating your
samples. You can compare this experiment with Thin
Layer
Chromatography setup for home. Perhaps you'll want to try
both setups and compare results.

The goal:

to achieve the best possible separation of the black marker
pigments using paper chromatography.

Paper chromatography uses
capillary force that move water or another solvent and the sample
up the paper strip. The most soluble compounds of the sample will go
farther the less soluble will
stay at the start line.

Using chromatography we can find out how many
components are in paint, inks, markers as well as in natural dyes, leaf
extracts. As long as mixture is colored we can see their
components. Colorless mixtures can also be separated with paper
chromatography, if we can visualize separated compounds with colored
chemical
reaction(s).

You'll
need:

Chromatography
paper(stationary phase) Coffee filter or blotting paper or paper towel
may also work. Different papers have different properties and will
separate substances more or less successfully. We had the best luck
with coffee filters.

Chromatography chamber. 1 liter glass jar
will do.

Paper clip.

skewer(or pencil).

Water soluble black marker(s).

Scissors.

Solvents
(mobile phase). There are many different solvents and their
combinations you'll need to try. We used: water, vinegar, acetone(nail
polish), rubbing alcohol, glass cleaner.

Materials
you need to do paper chromatography at home

Procedure:

Cut the chromatography strip out of the coffee
filter (or other paper, see above).

The
length of the strip depend on the height of the chamber the width does
not matter but it should be able freely get in the chromatography
chamber.

Draw a pencil line one inch from the
bottom of the strip. It will
be you start line. For our black marker experiment draw short
line along the start line. If you're trying to separate something else
put your sample(s) on the start line with small
capillary or toothpick.

Pour solvent into the chromatography
chamber
(jar) just to cover the bottom.

Put the strip of the chromatography paper
with sample(s) in the chromatography chamber, so that
bottom of the strip touches the solvent. Important! Start line should
stay above the solvent!

You'll see how solvent "climbs" up the
strip dragging the sample with it. Watch color spot going up the strip
and
possibly
separating on individual components.

Remove paper from the chamber when
solvent front are inch or two away
from the top or if it doesn't move up any more.

Mark where the solvent front is and where
are the middle of the color spots (if you lucky to get any).

Write the solvent combination and
proportions on the strip for future reference.

Selection of the right solvent combination for chromatography is the
very important, see images below. It's also the most time consuming
part of the process, so be patient. Try each available solvent and note
the result or
simply wright solvent's name on developed paper strip. Keeping
records will help you organize your data. Perfect
chromatography looks like colored spots with a space between them. It's
difficult to achieve such a result at home so don't be upset if you
only can
make a black marker to separate into the rainbow bands. It is actually
pretty good result. Unfortunately, good solvent combination for the
black water
marker may not work for other substances. If you want to
separate natural dyes or different markers or ink, you'll have to find
their best solvent composition.

Black marker chromatography using
water as a mobile phase. Black marker chromatography using
combination of glass cleaner and white vinegar in 10:1
proportion as a mobile phase.

Understanding
the results:

The
number of the spots or bands tells you how
many compounds are in your substance. Their color and the distance they
traveled might help you to identify those compounds. You can try to
find out which dyes were used in black marker using other markers from
the same package as a reference samples. If certain reference color
sample will travel the same distance (rf)
that one of the black marker colors both of them likely to be the same
chemical compound. You can't identify
the chemical substance by paper chromatography, but you can roughly
analyze the mixture with this simple and neat technique.